Answer: Option [C]The prokaryotic genetic system contains DNA but no histones. Prokaryotes are unicellular organisms without membrane-bound organelles. They lack a true nucleus. Instead, they have nucleoid, a genetic material without the nuclear envelope. In prokaryotes, the genetic material is single circular double-stranded DNA without histones.
Answer: Option [A]'One gene one enzyme theory' was given by Beadle and Tautum. The one gene - one enzyme hypothesis is the idea that genes act through the production of enzymes, with each gene responsible for producing a single enzyme that in turn affects a single step in a metabolic pathway. Beadle and Tatum proposed this concept.
Answer: Option [C]The correct answer is 22 chromosomes.
Meiosis contains 2 stages of division-
- Meiosis – 1
- Meiosis -2
Meiosis 1 is known as reductional division because in the anaphase stage of meiosis 1, segregation of homologous chromosomes takes place and each daughter cell receives one set of chromosomes.
Meiosis 2 is known as equational division, it is just like any mitotic division. The number of chromosomes in the cell which is dividing and the daughter cell remains the same.
So, if any cell contains 44 chromosomes then after meiosis - 1 each daughter cell will receive one set i.e. 22 chromosomes.
Answer: Option [C]The somatic chromosome complement in all human being is 22 pairs of autosomes and one pair of heterosomes.
Answer: Option [C]Depending upon size and centromere position the 46 chromosomes hhave been divided into a number of groups 7. Depending upon the position of centromere and relative length of two arms , human chromosome are of three types - metacentric , submetacentric and acrocentric . The photograph of chromosomes are artifically arranged in the order of descending length is seven group (A to G).
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